style: clean up and simply code for several classes (#253)

* FinalCommitment, GetQuorumRotationInfo, InstantSend8, LLMQ*, MasternodeConfig, Report

core/src/main/java/org/bitcoinj/masternode/owner/MasternodeConfig.java

@@ -9,13 +9,13 @@
 
 import java.io.*;
 import java.util.ArrayList;
+import java.util.List;
 
 /**
  * Created by Hash Engineering on 7/8/2018.
  */
 public class MasternodeConfig {
 
-
     public static class MasternodeEntry {
 
         private String alias;
@@ -76,7 +76,7 @@ public void setIp(String ip) {
     protected File masternodeConfigFile;
 
     public MasternodeConfig(File configFile) {
-        entries = new ArrayList<MasternodeEntry>();
+        entries = new ArrayList<>();
         masternodeConfigFile = configFile;
     }
 
@@ -94,15 +94,15 @@ public void add(String alias, String ip, String privKey, String txHash, String o
         entries.add(cme);
     }
 
-    public ArrayList<MasternodeEntry> getEntries() {
+    public List<MasternodeEntry> getEntries() {
         return entries;
     }
 
     public int getCount() {
         return entries.size();
     }
 
-    private ArrayList<MasternodeEntry> entries;
+    private final ArrayList<MasternodeEntry> entries;
 
     public boolean importFromFile(String fileToImport, StringBuilder strError) {
         try {
@@ -190,8 +190,7 @@ public boolean read(StringBuilder strError) {
         } catch (FileNotFoundException x) {
             strError.append(x.getMessage());
 
-            try {
-                FileOutputStream configFile = new FileOutputStream(masternodeConfigFile, true);
+            try (FileOutputStream configFile = new FileOutputStream(masternodeConfigFile, true)) {
                 String strHeader = "# Masternode config file\n" + "# Format: alias IP:port masternodeprivkey collateral_output_txid collateral_output_index\n" + "# Example: mn1 127.0.0.2:19999 93HaYBVUCYjEMeeH1Y4sBGLALQZE1Yc1K64xiqgX37tGBDQL8Xg 2bcd3c84c84f87eaa86e4e56834c92927a07f9e18718810b92e0d0324456a67c 0\n";
                 configFile.write(strHeader.getBytes());
                 return true; // Nothing to read, so just return

core/src/main/java/org/bitcoinj/quorums/FinalCommitment.java

@@ -33,6 +33,7 @@
 import java.io.OutputStream;
 import java.util.ArrayList;
 import java.util.Collections;
+import java.util.List;
 
 public class FinalCommitment extends SpecialTxPayload {
     @Deprecated
@@ -128,6 +129,7 @@ protected void parse() throws ProtocolException {
         length = cursor - offset;
     }
 
+    @Override
     protected void bitcoinSerializeToStream(OutputStream stream) throws IOException{
         bitcoinSerializeToStream(stream, isLegacy());
     }
@@ -189,6 +191,7 @@ public String getName() {
      *     }
      */
 
+    @Override
     public JSONObject toJson() {
         JSONObject result = new JSONObject();
         result.put("version", getVersion());
@@ -245,7 +248,7 @@ public boolean verify(StoredBlock block, ArrayList<Masternode> members, boolean
             return false;
 
         if(!params.getLlmqs().containsKey(LLMQParameters.LLMQType.fromValue(llmqType))) {
-            log.error("invalid llmqType " + llmqType);
+            log.error("invalid llmqType: {}", llmqType);
             return false;
         }
 
@@ -325,13 +328,10 @@ public boolean isNull()  {
             countValidMembers() > 0) {
             return false;
         }
-        if (quorumPublicKey.isValid() ||
-                !quorumVvecHash.isZero() ||
-                membersSignature.isValid() ||
-                quorumSignature.isValid()) {
-            return false;
-        }
-        return true;
+        return !quorumPublicKey.isValid() &&
+                quorumVvecHash.isZero() &&
+                !membersSignature.isValid() &&
+                !quorumSignature.isValid();
     }
 
     public boolean verifyNull()
@@ -342,11 +342,7 @@ public boolean verifyNull()
         }
         LLMQParameters llmqParameters = params.getLlmqs().get(LLMQParameters.LLMQType.fromValue(llmqType));
 
-        if (!isNull() || !verifySizes(llmqParameters)) {
-            return false;
-        }
-
-        return true;
+        return isNull() && verifySizes(llmqParameters);
     }
 
     public boolean verifySizes(LLMQParameters llmqParameters) {
@@ -361,6 +357,7 @@ public boolean verifySizes(LLMQParameters llmqParameters) {
         return true;
     }
 
+    @Override
     public Sha256Hash getHash() {
         try {
             UnsafeByteArrayOutputStream bos = new UnsafeByteArrayOutputStream(getMessageSize());
@@ -407,11 +404,11 @@ public BLSSignature getQuorumSignature() {
         return quorumSignature.getSignature();
     }
 
-    public ArrayList<Boolean> getSigners() {
+    public List<Boolean> getSigners() {
         return signers;
     }
 
-    public ArrayList<Boolean> getValidMembers() {
+    public List<Boolean> getValidMembers() {
         return validMembers;
     }
 

core/src/main/java/org/bitcoinj/quorums/GetQuorumRotationInfo.java

@@ -40,7 +40,7 @@ public GetQuorumRotationInfo(NetworkParameters params, byte [] payload) {
     }
 
     public GetQuorumRotationInfo(NetworkParameters params,
-                                 ArrayList<Sha256Hash> baseBlockHashes, Sha256Hash blockRequestHash, boolean extraShare) {
+                                 List<Sha256Hash> baseBlockHashes, Sha256Hash blockRequestHash, boolean extraShare) {
         super(params);
         this.baseBlockHashes = new ArrayList<>(baseBlockHashes.size());
         this.baseBlockHashes.addAll(baseBlockHashes);
@@ -73,7 +73,7 @@ public Sha256Hash getBlockRequestHash() {
         return blockRequestHash;
     }
 
-    public ArrayList<Sha256Hash> getBaseBlockHashes() {
+    public List<Sha256Hash> getBaseBlockHashes() {
         return baseBlockHashes;
     }
 

core/src/main/java/org/bitcoinj/quorums/InstantSendLock.java

@@ -118,6 +118,7 @@ public Sha256Hash getRequestId() {
         }
     }
 
+    @Override
     public Sha256Hash getHash() {
         try {
             UnsafeByteArrayOutputStream bos = new UnsafeByteArrayOutputStream(getMessageSize());